A crash course in how the internet works

Way back in 1995, I was a freshman at university. I had this new thing called “The Internet” at my fingertips.

It was cool, but I wanted to know how it worked. I asked someone, and they wouldn’t answer the question – mostly because they couldn’t answer!

Today, everyone knows and uses the internet, but people keep asking me questions about the basic concepts that make it go.

So, I figured it was about time to give a basic intro to how the internet actually works, including a simplified discussion of networks, IP addresses, ports, protocols, DNS, bandwidth, latency, and more!

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How to Block Apple Bonjour on your Local Network

Block Bonjour!Bonjour is Apple’s way of doing zero-configuration networking. It’s a bit of software that does three things:

  1. Service discovery on the local network (LAN)
  2. IP address assignment/sharing
  3. Hostname resolution

Normally, things like IP address assignment are handled by DHCP. With Bonjour, the idea is that all you have to do is plug your gizmos in, and turn them on. Bonjour will then “scan” the network, and all devices and services on the LAN will be automagically configured for you. Each gizmo will have an automatically configured IP and hostname, and you’re done.

This is great, except when you don’t want Bonjour to do its thing. Perhaps you have a mostly Windows/Linux LAN, or you want to restrict access to a certain group of computers on your LAN that are separated from the rest by a physical home router/firewall. Bonjour makes this rather difficult, since it sneaks by basic IP/MAC filtering you might set in your router.

So, how do you block Bonjour?

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